Biomolecules - Organic Chemistry - Chemistry Previous Year Questions

1

2009 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2009

In the reactions
[Reaction Scheme: D-glucose reacts with PhCHO/H+ to give [X]; D-glucose reacts with acetone/H+ to give [Y]]
the major products X and Y, respectively, are

A

[Structure: glucose with benzylidene acetal] and [Structure: glucose with acetonide]

B

[Structure: glucose with two benzylidene acetals] and [Structure: glucose with two acetonides]

C

[Structure: glucose with benzylidene acetal] and [Structure: glucose with two acetonides]

D

[Structure: glucose with two benzylidene acetals] and [Structure: glucose with acetonide]

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2

2011 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2011

The sequence of an mRNA molecule produced from a DNA template strand with the composition 5'-AGCTACACT-3' is

A

5'-AGUGUAGCU-3'

B

5'-UCGAUGUGA-3'

C

5'-AGTGATGCT-3'

D

5'-TCGATGTGA-3'

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3

2011 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2011

The structure of the dipeptide Ala-Pro derived from the natural amino acids is

A

\(\text{Structure: H2N-CH(CH3)-C(=O)-N(CH2CH2CH2)-C(=O)-OH}\)

B

\(\text{Structure: HO2C-CH(CH3)-NH-C(=O)-CH2CH2CH2NH}\)

C

\(\text{Structure: H2N-CH(CH3)-C(=O)-N(CH2CH2CH2)-C(=O)-OH}\)

D

\(\text{Structure: H2N-CH(CH3)-C(=O)-N(CH2CH2CH2)-C(=O)-OH}\)

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4

2011 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2011

Choose the most appropriate word from the options given below to complete the following sentence: Under ethical guidelines recently adopted by the Indian Medical Association, human genes are to be manipulated only to correct diseases for which ______________ treatments are unsatisfactory.

A

similar

B

most

C

uncommon

D

available

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5

2011 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2011

The horse has played a little known but very important role in the field of medicine. Horses were injected with toxins of diseases until their blood build up immunities. Then a serum was made from their blood. Serums to fight with diphtheria and tetanus were developed this way. It can be inferred from the passage, that horses were

A

given immunity to diseases

B

generally quite immune to diseases

C

given medicines to fight toxins

D

given diphtheria and tetanus serums

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6

2012 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2012

The average length of a typical α-helix comprised of 10 amino acids is

A

10 Å

B

15 Å

C

36 Å

D

54 Å

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7

2012 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2012

Number of thymine residues in a 5000 kb DNA containing 23% guanine residues is

A

2.70 × 10⁶

B

2.70 × 10⁷

C

1.35 × 10⁶

D

1.35 × 10⁷

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8

2012 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2012

A disaccharide that will not give Benedict's test and will not form osazone is

A

maltose

B

lactose

C

cellobiose

D

sucrose

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9

2013 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2013

The correct sequence of the amino acids present in the tripeptide given below is

A

Val-Ser-Thr

B

Val-Thr-Ser

C

Leu-Ser-Thr

D

Leu-Thr-Ser

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10

2014 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2014

Amongst the following, the structure of guanosine is

A

Option A

B

Option B

C

Option C

D

Option D

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11

2016 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2016

A disaccharide does NOT give a positive test for Tollen's reagent. Upon acidic hydrolysis, it gives an equimolar mixture of two different monosaccharides, both of which can be oxidized by bromine water. This disaccharide is

A

B

C

D

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12

2023 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2023

The compound which gives a fragment at \(m/z = 124 [M+H]^+\) is

A

B

C

D

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13

2024 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2024

Consider the following 1H-NMR (400 MHz, DMSO-d6) data of a compound: δ in ppm: 3.85 (s, 6H), 6.73 (t, J = 2.2 Hz, 1H), 7.1 (d, J = 2.2 Hz, 2H), and 13.05 (brs, 1H). The compound is

A

2,6-dimethoxybenzoic acid

B

3,5-dimethoxybenzoic acid

C

2,4-dimethoxybenzoic acid

D

2,4-dimethoxybenzoic acid (isomer)

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14

2024 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2024

Fischer presentation of D-(-)-fructose is given below. The correct structure of α-L-(+)-fructofuranose is

A

Furanose structure A

B

Furanose structure B

C

Furanose structure C

D

Furanose structure D

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15

2025 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2025

A disaccharide \(\mathbf{X}\) does NOT show mutarotation in aqueous solution. Acidic hydrolysis of \(\mathbf{X}\) affords two different monosaccharides. The disaccharide \(\mathbf{X}\) is

A

B

C

D

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16

2025 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2025

Partial hydrolysis of a pentapeptide yields all possible tripeptides and dipeptides. The dipeptides that are obtained upon hydrolysis are given below.
Val-Ala, Gln-His, Phe-Val and Ala-Gln
The total number of tripeptides obtained that contain ‘Ala’ as one of the amino acids is____ (in integer).

Check answer

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17

2007 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2007

Treatment of the pentapeptide Gly-Arg-Phe-Ala-Ala, in separate experiments, with the enzymes Trypsin, Chymotrypsin and Carboxypeptidase A respectively, gives

A

Gly-Arg + Phe-Ala-Ala ; Gly-Arg-Phe + Ala-Ala ; Gly-Arg-Phe-Ala + Ala

B

Gly-Arg-Phe + Ala-Ala ; Gly-Arg-Phe + Ala-Ala ; Gly-Arg-Phe-Ala + Ala

C

Gly-Arg + Phe-Ala-Ala ; Gly-Arg-Phe-Ala + Ala ; Gly-Arg-Phe + Ala-Ala

D

Gly-Arg + Phe-Ala-Ala ; Gly-Arg-Phe + Ala-Ala ; Gly + Arg-Phe-Ala + Ala

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18

2007 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2007

In the reaction, Compound X is

A

Adenine

B

Xanthine

C

2,6-diaminopurine

D

Adenosine

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19

2010 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2010

The decreasing order of isoelectric point for the following α-amino acids is
Lysine (I), Alanine (II), Glutamic acid (III)

A

I > II > III

B

II > I > III

C

III > I > II

D

I > III > II

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20

2015 · Chemistry · Organic Chemistry · Biomolecules

Chemistry (CY) 2015

The compound given below is a

A

sesterterpene

B

monoterpene

C

sesquiterpene

D

triterpene

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